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Cu/TiO_(2) Photocatalysts for CO_(2) Reduction: Structure and Evolution of the Cocatalyst Active Form

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Transactions of Tianjin University 2024年第2期30卷 140-151页

作者： Andrey A.Saraev Anna yu.Kurenkova denis D.Mishchenko Alexandr L.Trigub Evgeniy yu.Gerasimov Ekaterina A.Kozlova Boreskov Institute of Catalysis Lavrentieva Ave 5Novosibirsk 630090Russia Synchrotron Radiation Facility SKIF Boreskov Institute of CatalysisNikol’skiy Ave 1Kol’tsovo 630559Russia National Research Center “Kurchatov Institute”Kurchatova Sq 1Moscow 123182Russia

Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV-vis diff use refl ectance spectroscopy, high-resolution transmis- sion electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. It was found that copper exists in different states (Cu 0 , Cu^(+) , and Cu^(2+) ), the content of which depends on the TiO_(2) calcination temperature and copper loading. The optimum composition of the cocatalyst has a photocatalyst based on TiO_(2) calcined at 700℃ and modified with 5 wt% copper, the activity of which is 22 μmol/(h·g cat ) (409 nm). Analysis of the photocatalysts after the photocatalytic reaction disclosed that the copper metal on the surface of the calcined TiO_(2) was gradually converted into Cu_(2) O during the photocatalytic reaction. Meanwhile, the metallic copper on the surface of the noncalcined TiO_(2) did not undergo any trans- formation during the reaction.

关键词： Photocatalysis Photocatalytic CO_(2)conversion Visible light Titanium dioxide Copper Copper oxides Methane formation Photocatalyst transformation

Averaged Dynamics of Fluids near the Oscillating Interface in a Hele-Shaw Cell

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Fluid Dynamics & Materials Processing 2024年第4期20卷 847-857页

作者： Anastasia Bushueva Olga Vlasova denis Polezhaev Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia

The steady flow in a Hele-Shaw cell filled with fluids with a high viscosity contrast in the presence of fluid oscillations is experimentally studied.The control of oscillatory dynamics of multiphase systems with interfaces is a challenging technological problem.We consider miscible(water and glycerol)and immiscible(water and high-viscosity silicone oil PMS-1000)fluids under subsonic oscillations perpendicular to the interface.Observations show that the interface shape depends on the amplitude and frequency of oscillations.The interface is undisturbed only in the absence of oscillations.Under small amplitudes,the interface between water and glycerol widens due to mixing.When the critical amplitude is reached,the interface becomes unstable to the fingering instability:Aqueous fingers penetrate the high-viscosity glycerol and induce intensive mixing of miscible fluids and associated decay of the instability.After the disappearance of the fingers,the interface takes a U-shape in the central part of the cell.A similar effect is observed for immiscible fluids:The oscillating interface tends to bend to the side of a high-viscosity fluid.Again,when the critical amplitude is reached,the fingering instability arises at the convex interface.This paper focuses on the causes of bending of the initially undisturbed interface between miscible or immiscible fluids.For this purpose,we measure the steady flow velocity near the interface and in the bulk of a high-viscosity fluid using Particle Image Velocimetry(PIV).

关键词： Hele-Shaw cell oscillations steady flow miscible fluids immiscible fluids interface

Smoothed particle hydrodynamics based numerical study of hydroplaning considering permeability characteristics of runway surface

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 319-333页

作者： Yang YANG Xingyi ZHU denis JELAGIN Alvaro GUARIN Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China Auto Engineering Research Institute BYD Auto Industry Company LimitedShenzhen 518118China Department of Civil and Architectural Engineering KTH Royal Institute of TechnologyStockholm 10044Sweden

The presence of water films on a runway surface presents a risk to the landing of aircraft.The tire of the aircraft is separated from the runway due to a hydrodynamic force exerted through the water film,a phenomenon called hydroplaning.Although a lot of numerical investigations into hydroplaning have been conducted,only a few have considered the impact of the runway permeability.Hence,computational problems,such as excessive distortion and computing efficiency decay,may arise with such numerical models when dealing with the thin water film.This paper presents a numerical model comprising of the tire,water film,and the interaction with the runway,applying a mathematical model using the smoothed particle hydrodynamics and finite element(SPH-FE)algorithm.The material properties and geometric features of the tire model were included in the model framework and water film thicknesses from 0.75 mm to 7.5 mm were used in the numerical simulation.Furthermore,this work investigated the impacts of both surface texture and the runway permeability.The interaction between tire rubber and the rough runway was analyzed in terms of frictional force between the two bodies.The SPH-FE model was validated with an empirical equation proposed by the National Aeronautics and Space Administration(NASA).Then the computational efficiency of the model was compared with the traditional coupled Eulerian-Lagrangian(CEL)algorithm.Based on the SPH-FE model,four types of the runway(Flat,SMA-13,AC-13,and OGFC-13)were discussed.The simulation of the asphalt runway shows that the SMA-13,AC-13,and OGFC-13 do not present a hydroplaning risk when the runway permeability coefficient exceeds 6%.

关键词： SPH-FE approach hydroplaning numerical simulation surface texture runway surface reconstruction

Comparison of ERA5 turbulent fluxes at the air-sea interface with measurements from a wave-following platform

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Atmospheric and Oceanic Science Letters 2024年第3期17卷 32-36页

作者： Said Benjeddou denis Bourras Christopher Luneau Aix Marseille Universite National Center for Scientific ResearchMediterranean Institute of OceanographyMarseilleFrance Observatory of the Sciences of the Universe Pytheas Institute National Center for Scientific ResearchMarseilleFrance

Turbulent fluxes at the air-sea interface were estimated with data collected in 2011-2020 with a low-profile platform named OCARINA during eight experiments in five regions:2011,2015,and 2016 in the Iroise Sea;2012 in the tropical Atlantic;2014 in the Chilie-Peru upwelling;2017 and 2018 in the Mediterranean Sea,and 2018 and 2020 in Barbados.The observations were carried out with moderate winds(2-10 m s^(-1))and average wave heights of 1.5 m.In this study,the authors used the fluxes calculated by the bulk method using OCARINA-sampled data as the input.These data can validate the fluxes estimated from ERAS reanalysis data.The OCARINA and ERA5 data were taken concomitantly.To do this,the authors established an algorithm to extract the OCARINA data as closely as possible to the reanalysis data in time and position.The measurements of the OCARINA platform can conclude on the relevance of the widely used reanalysis data.

关键词： Ocarina ECMWF ERA5 Turbulent fluxes Louis formulation

Differential Game Model of Resource Extraction with Continuous and Dynamic Updating

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Journal of the Operations Research Society of China 2024年第1期12卷 51-75页

作者： Ovanes Petrosian Tihomirov denis Jiang-Jing Zhou Hong-Wei Gao School of Mathematics Harbin Institute of TechnologyHarbin150001HeilongjiangChina School of Automation Qingdao UniversityQingdao266071ShandongChina Faculty of Applied Mathematics and Control Processes Saint-Petersburg State UniversitySaint PetersburgRussia National Research University"High School of Economics" Saint-PetersburgRussia School of Mathematics and Statistics Qingdao UniversityQingdao266071ShandongChina

This paper is devoted to a new class of differential games with continuous and dynamic updating.The direct application of resource extraction in a case of dynamic and continuous updating is considered.It is proved that the optimal control(cooperative strategies)and feedback Nash equilibrium strategies uniformly converge to the corresponding strategies in the game model with continuous updating as the number of updating instants converges to infinity.Similar results are presented for an optimal trajectory(cooperative trajectory),equilibrium trajectory and corresponding payoffs.

关键词： Differential games Dynamic updating Continuous updating Optimal control Feedback Nash equilibrium

The penetration depth of atomic radicals in tubes with catalytic surface properties

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Plasma Science and Technology 2024年第7期26卷 157-164页

作者： Domen PAUL Miran MOZETIC Rok ZAPLOTNIK Alenka VESEL Gregor PRIMC denis DONLAGIC Jozef Stefan Institute Jamova Cesta 39Ljubljana 1000Slovenia Jozef Stefan International Postgraduate School Jamova Cesta 39Ljubljana 1000Slovenia Faculty of Electrical Engineering and Computer Science University of MariborKoroska Cesta 46Maribor 2000Slovenia

Catalysis of molecular radicals is often performed in interesting experimental configurations.One possible configuration is tubular geometry.The radicals are introduced into the tubes on one side,and stable molecules are exhausted on the other side.The penetration depth of radicals depends on numerous parameters,so it is not always feasible to calculate it.This article presents systematic measurements of the penetration depth of oxygen atoms along tubes made from nickel,cobalt,and copper.The source of O atoms was a surfatron-type microwave plasma.The initial density of O atoms depended on the gas flow and was 0.7×10^(21)m^(-3),2.4×10^(21)m^(-3),and 4.2×10^(21)m^(-3)at the flow rates of 50,300,and 600 sccm,and pressures of 10,35,and 60 Pa,respectively.The gas temperature remained at room temperature throughout the experiments.The dissociation fraction decreased exponentially along the length of the tubes in all cases.The penetration depths for well-oxidized nickel were 1.2,1.7,and 2.4 cm,respectively.For cobalt,they were slightly lower at 1.0,1.3,and 1.6 cm,respectively,while for copper,they were 1.1,1.3,and 1.7 cm,respectively.The results were explained by gas dynamics and heterogeneous surface association.These data are useful in any attempt to estimate the loss of molecular fragments along tubes,which serve as catalysts for the association of various radicals to stable molecules.

关键词： oxygen plasma penetration depth catalysis heterogeneous surface recombination atom loss

Interactive mechanism and friction modelling of transient tribological phenomena in metal forming processes: A review

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Friction 2024年第3期12卷 375-395页

作者： Xiao YANG Heli LIU Lemeng ZHANG Yiran HU denis J.POLITIS Mohammad M.GHARBI Liliang WANG Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK Department of Mechanical and Manufacturing Engineering University of CyprusNicosia 1678Cyprus Quaker Houghton Deutschland GmbH Dortmund 44319Germany

The accurate representation of tribological boundary conditions at the tool–workpiece interface is crucial for analysis and optimization of formability,material flow,and surface quality of components during metal forming processes.It has been found that these tribological conditions vary spatially and historically with process parameters and contact conditions.These time-dependent tribological behaviours are also known as transient tribological phenomena,which are widely observed during forming processes and many other manufacturing application scenarios.However,constant friction values are usually assigned to represent complex and dynamic interfacial conditions,which would introduce deviations in the relevant predictions.In this paper,transient tribological phenomena and the contemporary understanding of the interaction between friction and wear are reviewed,and it has been found that these phenomena are induced by the transitions of friction mechanisms and highly dependent on complex loading conditions at the interface.Friction modelling techniques for transient behaviours for metal forming applications are also reviewed.To accurately describe the evolutionary friction values and corresponding wear during forming,the advanced interactive friction modelling has been established for different application scenarios,including lubricated condition,dry sliding condition(metal-on-metal contact),and coated system.

关键词： transient tribological phenomena interactive friction mechanism modelling techniques metal forming

Gene-modified leucoconcentrate for personalized ex vivo gene therapy in a mini pig model of moderate spinal cord injury

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Neural Regeneration Research 2021年第2期16卷 357-361页

作者： Rustem R.Islamov Farid V.Bashirov Mikhail E.Sokolov Andrei A.Izmailov Filip O.Fadeev Vage A.Markosyan Maria A.Davleeva Olga V.Zubkova Maxim M.Smarov denis yu.logunov Boris S.Naroditskyi Ilnur I.Salafutdinov Albert A.Rizvanov Ramil G.Turaev Kazan State Medical University KazanRussia Gamaleya Research Institute of Epidemiology and Microbiology MoscowRussia Kazan Federal University KazanRussia The Republican Blood Center of the Ministry of Health of the Republic of Tatarstan KazanRussia

We previously demonstrated that gene-modified umbilical cord blood mononuclear cells overexpressing a combination of recombinant neurotrophic factors are a promising therapeutic approach for cell-mediated gene therapy for neurodegenerative diseases,neurotrauma,and stroke.In this study,using a mini pig model of spinal cord injury,we proposed for the first time the use of gene-modified leucoconcentrate prepared from peripheral blood in the plastic blood bag for personalized ex vivo gene therapy.Leucoconcentrate obtained from mini pig peripheral blood was transduced with a chimeric adenoviral vector(Ad5/35 F)that carried an enhanced green fluorescent protein(EGFP)reporter gene in the plastic blood bag.The day after blood donation,the mini pigs were subjected to moderate SCI and four hours post-surgery they were intravenously autoinfused with gene-modified leucoconcentrate.A week after gene-modified leucoconcentrate therapy,fluorescent microscopy revealed EGFP-expressing leucocytes in spinal cord at the site of contusion injury.In the spleen the groups of EGFP-positive cells located in the lymphoid follicles were observed.In vitro flow cytometry and fluorescent microscopy studies of the gene-modified leucoconcentrate samples also confirmed the production of EGFP by leucocytes.Thus,the efficacy of leucocytes transduction in the plastic blood bag and their migratory potential suggest their use for temporary production of recombinant biologically active molecules to correct certain pathological conditions.This paper presents a proof-of-concept of simple,safe and effective approach for personalized ex vivo gene therapy based on gene-modified leucoconcentrate autoinfusion.The animal protocols were approved by the Kazan State Medical University Animal Care and Use Committee(approval No.5)on May 27,2014.

关键词： chimeric Ad5/35F virus enhanced green fluorescent protein gene-modified leucoconcentrate mini pig peripheral blood personalized ex vivo gene therapy plastic blood bag spinal cord injury

Comparison of ERA5 turbulent fluxes at the air-sea interface with measurements from a wave-following platform

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Atmospheric and Oceanic Science Letters 2024年第3期 34-38页

作者： Sa?d Benjeddou denis Bourras Christopher Luneau Aix Marseille Université National Center for Scientific ResearchMediterranean Institute of Oceanography Observatory of the Sciences of the Universe Pythéas Institute National Center for Scientific Research

Turbulent fluxes at the air-sea interface were estimated with data collected in 2011-2020 with a low-profile platform named OCARINA during eight experiments in five regions:2011,2015,and 2016 in the Iroise Sea;2012 in the tropical Atlantic;2014 in the Chilie-Peru upwelling;2017 and 2018 in the Mediterranean Sea,and 2018 and 2020 in Barbados.The observations were carried out with moderate winds(2-10 m s-1) and average wave heights of 1.5 m.In this study,the authors used the fluxes calculated by the bulk method using OCARINA-sampled data as the input.These data can validate the fluxes estimated from ERAS reanalysis data.The OCARINA and ERA5 data were taken concomitantly.To do this,the authors established an algorithm to extract the OCARINA data as closely as possible to the reanalysis data in time and position.The measurements of the OCARINA platform can conclude on the relevance of the widely used reanalysis data.

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